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Horizon
Treadmill

Model # 4.2T Official Horizon treadmill

Here are the diagrams and repair parts for Official Horizon 42T treadmill, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 145 parts  |
Power Board SZTM115MCB
#M03

Treadmill assy diagram

Power board

Part #SZTM115MCB

Replaced by #032669-IF

?
Manufacturer substitution
This part replaces SZTM115MCB. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$220.62 | 
$10.00 OFF Phone Price : $230.62
In Stock
Socket MC0703023
#P11

Treadmill assy diagram

Socket

Part #MC0703023

Replaced by #019749-A

?
Manufacturer substitution
This part replaces MC0703023. Substitute parts can look different from the original.
This item is not returnable
$9.62 | 
9% OFF Phone Price : $10.62
In Stock
Wheel MB0103006B
#L05

Treadmill assy diagram

Wheel

Part #MB0103006B

Replaced by #000021-B

?
Manufacturer substitution
This part replaces MB0103006B. Substitute parts can look different from the original.
This item is not returnable
$5.25
In Stock
Bolt ME0104098
#R04

Treadmill assy diagram

Bolt

Part #ME0104098

Replaced by #004496-00

?
Manufacturer substitution
This part replaces ME0104098. Substitute parts can look different from the original.
This item is not returnable
$5.57
In Stock
Safety Key MR0004003A
#AN3

Treadmill assy diagram

Safety key

Part #MR0004003A

Replaced by #051345-A

?
Manufacturer substitution
This part replaces MR0004003A. Substitute parts can look different from the original.
This item is not returnable
$30.87 | 
14% OFF Phone Price : $35.87
In Stock
Console Cable MC0502044A
#P06

Treadmill assy diagram

Console cable

Part #MC0502044A

Replaced by #002103-A

?
Manufacturer substitution
This part replaces MC0502044A. Substitute parts can look different from the original.
$25.94
In Stock
Ac Cord MC0504054A
#P16

Treadmill assy diagram

Ac cord

Part #MC0504054A

Replaced by #002169-A

?
Manufacturer substitution
This part replaces MC0504054A. Substitute parts can look different from the original.
$46.34 | 
10% OFF Was : $51.49
In Stock
Sensor MC0510031D
#P14

Treadmill assy diagram

Sensor

Part #MC0510031D

Replaced by #002248-D

?
Manufacturer substitution
This part replaces MC0510031D. Substitute parts can look different from the original.
$8.16
In Stock
Bolt MJ3022012A
#Z09

Treadmill assy diagram

Bolt

Part #MJ3022012A

Replaced by #008626-B

?
Manufacturer substitution
This part replaces MJ3022012A. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock
Screw MZE0112034
#K10

Treadmill assy diagram

Screw

Part #MZE0112034

Replaced by #004724-00

?
Manufacturer substitution
This part replaces MZE0112034. Substitute parts can look different from the original.
This item is not returnable
$2.88
In Stock

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

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Why won't my treadmill power up?

Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor co…

Read more

Why is my treadmill's walking belt off center?

Main causes: rear roller out of alignment, damaged walking belt, bad roller…

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Why won't my treadmill start even though the console display works?

Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor…

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Why is my treadmill's heart rate sensor not accurate?

Main causes: faulty sensors, wiring failure, bad control console…

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Why does my treadmill have no display?

Main causes: bad control console, wiring failure, bad motor control board…

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Why does my treadmill's walking belt slow down?

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor…

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Why is my treadmill's walking belt slipping?

Main causes: damaged walking belt, improper belt tension, bad roller bearing…

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Repair guides for treadmills

These step-by-step repair guides will help you safely fix what’s broken on your treadmill.

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How to replace a treadmill motor controller

How to replace a treadmill motor controller

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the…

Read more
Repair difficulty
Time required
 15 minutes or less
How to replace a treadmill walking belt

How to replace a treadmill walking belt

A worn walking belt will begin to slow down during use. If your treadmill walking belt is worn out, replace it using the…

Read more
Repair difficulty
Time required
 45 minutes or less
How to replace a treadmill drive motor

How to replace a treadmill drive motor

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn'…

Read more
Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your fitness & exercise

Use the advice and tips in these articles and videos to get the most out of your treadmill.

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Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

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